1. Field of the Invention
The present invention relates to a carrier device and an inkjet printer having the same, and a carrying method.
2. Description of the Related Art
Carrier devices for carrying a long web of medium, and inkjet printers for printing an intended image by discharging ink from an ink head onto a medium being carried by a carrier device have been known in the art.
Carrier devices include roll-to-roll-type carrier devices, for example. With roll-to-roll-type carrier devices, a long web of medium, rolled in a roll, is unrolled to be carried, and the medium having been carried is re-rolled into a roll.
An inkjet printer having a roll-to-roll-type carrier device performs an intended printing operation by discharging ink onto a medium while moving the ink head in a direction perpendicular to the medium-carrying direction (secondary scanning direction).
FIGS. 27A to 27C show a known inkjet printer 200 having a roll-to-roll-type carrier device 215. As shown in FIG. 27A, the carrier device 215 includes a roll medium accommodating section 208, a carrying section 227 (see FIG. 27C), a dancer roller 212, and a re-rolling section 210. As shown in FIG. 27C, the carrying section 227 includes grid rolls 224 provided on a platen 222, and pinch rolls 226 arranged to be in contact with the grid rolls 224. By driving the grid rolls 224 with a medium 300 sandwiched between the grid rolls 224 and the pinch rolls 226, the medium 300 unrolled from a roll medium RM is carried in the secondary scanning direction. The carrying section 227 carries the medium 300 sandwiched between the grid rolls 224 and the pinch rolls 226 in the secondary scanning direction.
The dancer roller 212 gives a predetermined tension on the long web of the medium 300 being carried. With the dancer roller 212 applying a tension on the medium 300, it is possible to appropriately carry the medium 300 onto the platen 222 without wrinkling or slacking the medium 300, and it is possible to re-roll the medium 300 having been carried without the medium 300 running askew and without wrinkling or slacking the medium 300.
That is, with the carrier device 215, the medium 300 unrolled from the roll medium RM disposed in the roll medium accommodating section 208 is carried by the grid rolls 224, and the medium 300 having been carried is re-rolled by the re-rolling section 210 while a predetermined tension is applied on the medium 300 by the dancer roller 212.
However, with the inkjet printer 200 having such a conventional carrier device 215, a center axis RO of the roll medium RM disposed in the roll medium accommodating section 208 may not be parallel to the X axis or a center axis LO of the re-rolling section 210 may not be parallel to the X axis due to part precision errors in various parts, and the like.
Where the center axis RO of the roll medium RM or the center axis LO of the re-rolling section 210 is not parallel to the X axis, the length of a right side edge 300a and the length of a left side edge 300b of the medium 300 unrolled from the roll medium RM differ from each other. Therefore, even with a predetermined tension applied on the medium 300 by the dancer roller 212, the medium 300 is re-rolled askew at the re-rolling section 210. When a print result on the medium 300 is transferred by using the medium 300 having been re-rolled askew, for example, problems will arise such as a misalignment of the transfer of the print result, thus failing to properly perform the transfer process.